Process for the preparation of a metal-organic compound comprising at least one imine ligand

ABSTRACT

A process for the preparation of a metal-organic compound, comprising at least one imine ligand, characterized in that an imine ligand according to formula (1) or the HA adduct thereof, wherein HA represents an acid, of which H represents its proton and A its conjugate base, is contacted with a metal-organic reagent of formula (2) in the presence of at least 1, respectively at least 2 equivalents of a base, with Y═N—R as formula (1), wherein Y is selected from a substituted carbon, or nitrogen atom and R represents a substituent, and with M v (L 1 )k(L 2 )l(L 3 )m(L 4 )n x  as formula (2), wherein: M represents a group 4 or group 5 metal ion, V represents the valency of the metal ion, being 3, 4 or 5, L 1 , L 2 , L 3 , and L 4  represent a ligand or a group 17 halogen atom on M and may be equal or different, X represents a group 17 halogen atom, k, l, m, n=0, 1, 2, 3, 4 with k+l+m+n+l=V. The invention further relates to a process for the preparation of a polyolefin by making a metal-organic compound according to the process of the invention, wherein the base is an olefin polymerisation compatible base, which metal-organic compound is activated anywhere in, or before a polymerisation reactor.

This application is the US national phase of international applicationPCT/EP2004/008844, filed 3 Aug. 2004, which designated the U.S. andclaims benefit of EP 03077434.3, filed 4 Aug. 2003, the entire contentof which is hereby incorporated by reference.

The invention relates to a process for the preparation of anmetal-organic compound comprising at least one imine ligand according toformula 1. Metal-organic compounds thus produced are typically used asprecatalyst in the production of polyolefins. Imine ligands for theseprecatalyst can be guanidine, iminoimidazoline, or ketimine, themanufacturing of which is described in WO 02070569 and U.S. Pat. No.6,114,481 respectively. Two procedures for the preparation of aguanidine or iminoimidazoline comprising metal-organic compound aredisclosed in WO 02070569, starting from the respective ligands andCpTiCl₃.

In the first procedure, the ligand is contacted at −80° C. withbutyllithium in THF and warmed room temperature. Then, this mixture isfurther contacted with CpTiCl₃ at −80° C. and warmed up to roomtemperature. After removal of the THF, the metal-organic compound formedis extracted with boiling toluene, followed by its isolation by means ofcrystallization. The resulting product is further benzylated in asubsequent reaction step.

In the second procedure CpTiCl₃ is contacted with 3 equivalents ofbenzylmagnesiumbromide (BzMgBr) in diethylether at 0° C. After warmingup to room temperature and stirring for 12 hours, the thus formedCpTiBz₃ was extracted and subsequently crystallized. Then CpTiBz₃ wascontacted with the iminoimidazoline ligand in toluene at 50° C. for 2hours. The metal-orgainc compound obtained, was isolated aftercrystallization from boiling hexane. A disadvantage of this process isthat at least two steps are required, which have to be carried out atlow temperature and require some solvent changes.

Purpose of the present invention is to provide a widely applicablemethod for the manufacturing of a metal-organic compound from an imineand a metal-organic precursor in one step.

This aim is achieved in that an imine ligand according to formula 1, orthe HA adduct thereof, wherein HA represents an acid, of which Hrepresents its proton and A its conjugate base, is contacted with ametal-organic reagent of formula 2 in the presence of at least 1,respectively 2 equivalents of base, whereinY═N—R  (formula 1)wherein Y is selected from a substituted carbon, or nitrogen atom and Rrepresents a proton, a protic or an aprotic substituent, and:M^(v)(L₁)_(k)(L₂)_(l)(L₃)_(m)(L₄)_(n)X  (formula 2)wherein:M represents a group 4 or group 5 metal ionV represents the valency of the metal ion, being 3, 4 or 5L₁, L₂, L₃, and L₄ represent ligands on M and may be equal or differentX represents a group 17 halogen atomk, l, m, n=0, 1, 2, 3, 4 with k+l+m+n+l=V

With the method of the invention a metal-organic compound, suitable asprecatalyst in olefin polymerisation, is prepared in one step. Anadditional advantage of the method of the invention is, that during theprocess hardly any by-products are formed, so that further purificationis not necessary (or very limited with respect to state of the artprocesses). The metal-organic compound prepared by the method of theinvention has a higher purity than a metal-organic compound prepared viaknown production processes and can be used as such in olefinpolymerisation processes. An additional advantage of the process of theinvention is that the process can be carried out at room temperature,whereas the reaction of the N-trialkylsilyl substituted imine ligandwith the metal-organic reagent has to be often carried out at elevatedtemperatures.

The imine derivative or its HA adduct, as represented in formula 1, issubstituted by an Y- and an R group. In the method of the invention, theY group consists of a substituted carbon, or nitrogen atom. If Yrepresents a substituted carbon atom, the number of substituents is 2.If Y represents a substituted nitrogen atom, the number of substituentsis 1

Substituents on carbon, or nitrogen may be equal or different,optionally linked with each other, optionally having heteroatoms.Substituents may be protic or aprotic. A protic substituent is definedhere as a substituent, which has at least one, group 15 or group 16 atomcontaining at least one proton.

Examples of protic substituents include C₁-C₂₀ linear, branched orcyclic hydrocarbyl radicals, substituted with a group 15 or 16 atombearing at least one hydrogen atom. Preferred protic substituentsinclude phenolic radicals, pyrrolic radicals, indolic radicals, andimidazolic radicals.

The substituent is called aprotic if the substituent lacks a groupcontaining a group 15 or group 16 atom bearing a proton. Anunsubstituted aprotic hydrocarbyl radical can be a C₁-C₂₀ linear,branched or cyclic radical, a hydrogen atom, a halogen atom, a C₁₋₈alkoxy radical, a C₆₋₁₀ aryl or aryloxy radical, an amido radical, or aC₁₋₂₀ hydrocarbyl radical unsubstituted or substituted by a halogenatom, a C₁₋₈ alkoxy radical, a C₆₋₁₀ aryl or aryloxy radical, an amidoradical, a silyl radical, or a germanyl.

The substituent R can be H, or being equal as these for the substituenton Y.

Examples of imine ligands according to formula (I) thus include:guanidines, iminoimidazolines, phosphinimines, phenolimines,pyrroleimines, indoleimines and imidazoleimines.

R may be linked with Y, thus forming a ring system, optionallycomprising heteroatoms, or optionally comprising functional groups.Examples of ligands comprising such ring systems include:8-hydroxyquinoline, 8-aminoquinoline, 8-phosphinoquinoline,8-thioquinoline, 8-hydroxyquinaldine, 8-aminoquinaldine,8-phosphinoquinaldine, 8-thioquinaldine and 7-azaindole or indazole.

In a preferred embodiment of the method of the invention, R represents ahydrogen atom and Y is selected from the group consisting of: asubstituent according to formula 3:

wherein each of Sub¹ and Sub² is independently selected from the groupconsisting of hydrocarbyl radicals having from 1 to 30 carbon atoms;silyl radicals, (substituted) amido radicals and (substituted) phosphidoradicals, and wherein Sub¹ and Sub² may be linked with each other toform a ring system.

Preferably Sub¹ and Sub² are each independently selected from the groupof C1-C20 hydrocarbyl radicals, or substituted amido radicals optionallylinked by a bridging moiety.

In the process of the invention, HA represents an acid, of which Hrepresents its proton and A its conjugate base. Examples of A arehalogenides, such as fluoride, chloride, bromide, or iodide, sulfate,hydrogensulfate, phosphate, hydrogenphosphate, dihydrogenphosphate,carbonate, hydrogencarbonate, aromatic or aliphatic carboxylates,cyanide, tetrafluoroborate, (substituted) tetraphenylborates,fluorinated tetraarylborates, alkyl or aryl sulfonates.

The “number of equivalents of a base” is understood to be the amount ofequivalents with respect to the number of imine ligands, orfunctionalities in the event that one ligand comprises more than oneimine functionality. With “at least 1, respectively 2 equivalents of abase”, and lateron in the application “at least 3, respectively 4equivalents of a base”, is meant that at least 1, respectively 3equivalents of a base are required when the imine ligand as such isused, but that at least 2, respectively 4 equivalents are required, incase the HA adduct of the imine ligand is used.

The metal-organic reagent used in the method of the invention is areagent according to formula 2. In this formula L₁ to L₄ canindependently be a monoanionic ligand or a group 17 halogen atom.

Examples of monoanionic ligands are: halides like a fluoride, chloride,bromide or iodide, (un)substituted aliphatic or aromatic hydrocarbyls,like C₁-C₂₀ hydrocarbyl radicals, aryloxy or alkyloxy,cyclopentadienyls, indenyls, tetrahydroindenyls, fluorenyls,tetrahydrofluorenyls, and octahydrofluorenyls, amides, phosphides,sulfides, ketimides, guanidines, iminoimidazolines, phosphinimides,substituted imines, like (hetero)aryloxyimines, pyrroleimines,indoleimines, imidazoleimines or (hetero)aryloxides.

Preferred monoanionic ligands include: fluoride, chloride, bromide,iodide, C₁-C₂₀ hydrocarbyl radicals, cyclopentadienyl, C₁-C₂₀hydrocarbyl substituted cyclopentadienyls, halogen substituted C₁-C₂₀hydrocarbyl substituted cyclopentadienyls, indenyl, C₁-C₂₀ hydrocarbylsubstituted indenyls, halogen substituted C₁-C₂₀ hydrocarbyl substitutedindenyls, fluorenyls, C₁-C₂₀ hydrocarbyl substituted fluorenyls, halogensubstituted C₁-C₂₀ hydrocarbyl substituted fluorenyls, C₁-C₄₅substituted phosphinimides, C₁-C₂₀ substituted ketimides, C₁-C₃₀substituted guanidines, C₁-C₃₀ iminoimidazolines.

Most preferably monoanionic ligands are selected from fluoride,chloride, bromide, iodide, cyclopentadienyl, C₁-C₂₀ hydrocarbyl(optionally containing hetero- or group 17 halogen atoms), substitutedcyclopentadienyls, indenyl, C₁-C₂₀ hydrocarbyl substituted indenyls, andhalogen substituted C₁-C₂₀ hydrocarbyl substituted indenyls.

Depending on the valency of the metal of the metal-organic reagent,preferably at least one L_(i), L₂, L₃, or L₄ represents a group 17 atom.If the valency of the metal V=3, one or two ligands L may represent agroup 17 atom. If V=4, two or three ligands L may represent a group 17atom. If V=5, two to four ligands L may represent a group 17 atom.Preferred group 17 atom ligands are fluoride, chloride, bromide oriodide atoms. The most preferred group 17 atom ligand is chloride. In amost preferred embodiment, at least one of the ligands L is chosen fromcyclopentadienyl, C₁-C₂₀ hydrocarbyl (optionally containing hetero- orgroup 17 halogen atoms), substituted cyclopentadienyls, indenyl, C₁-C₂₀hydrocarbyl substituted indenyls, and halogen substituted C₁-C₂₀hydrocarbyl substituted indenyls. C₁-C₂₀ hydrocarbyl (optionallycontaining hetero- or group 17 halogen atoms) also includes aryloxy oralkyloxy, octahydrofluorenyls, amides, phosphides, sulfides, ketimides,guanidines, iminoimidazolines, phosphinimides, substituted imines, like(hetero)aryloxyimines, pyrroleimines, indoleimines, imidazoleimines and(hetero)aryloxides.

In the method of the invention an imine ligand or the HA adduct thereofaccording to formula 1, is contacted with a metal-organic reagent offormula 2 in the presence of at least 1, respectively 2, equivalents ofa base. Examples of a base include, carboxylates (for example potassiumacetate), fluorides, hydroxides, cyanides, amides and carbonates of Li,Na, K, Rb, Cs, ammonium and the group 2 metals Mg, Ca, & Ba, the alkalimetal (Li, Na, K, Rb, Cs) phosphates and the phosphate esters (eg. C₆H₅OP(O)(ONa)₂ and related aryl and alkyl compounds) and their alkoxidesand phenoxides, thallium hydroxide, alkylammonium hydroxides andfluorides. Some of these bases may be used in conjunction with a phasetransfer reagent, such as for example tetraalkylammonium-,tetraalkylphosphonium salts or crown ethers.

Also stronger bases may be applied, like carbanions such ashydrocarbanions of group 1, group 2, group 12 or group 13 elements. Alsothe metallic alkalimetals of group 1 may be applied as a base.

Preferred bases include amines, phosphanes, organolithium compounds, ororganomagnesium compounds, alkali metals, group 1 hydrides or group 2hydrides

More preferred bases are mono-, di-, or tri-, alkylamines or aromaticamines, organolithium compounds, organomagnesium compound, sodiumhydride or calciumhydride. Under aromatic amines is understood in thisapplication compounds having a nitrogen atom in an aromatic ring systemor mono-, di-, or triarylamines.

Even more preferred bases are triethylamine, pyridine, tripropylamine,tributylamine, 1,4-diaza-bicyclo[2.2.2]octane, pyrrolidine or piperidineorganolithium compounds, or organomagnesium compounds. Examples oforganomagnesium compounds are: methylmagnesiumhalides,phenylmagnesiumhalides, benzylmagnesiumhalides,biphenylmagnesiumhalides, naphtylmagnesiumhalides,tolylmagnesiumhalides, xylylmagnesiumhalides, mesitylmagnesiumhalides,dimethylresorcinolmagnesiumhalides, N,N-dimethylanilinemagnesiumhalides,dimethylmagnesium, diphenylmagnesium, dibenzylmagnesium,bis(biphenyl)magnesium, dinaphtylmagnesium, ditolylmagnesium,dixylylmagnesium, dimesitylmagnesium, bis(dimethylresorcinol)magnesium,bis(N,N-dimethylaniline)magnesium.

Examples of organolithium compounds are: methyllithium, phenyllithium,benzyllithium, biphenyllithium, naphtyllithium,dimethylresorcinollithium, N,N-dimethylanilinelithium.

In order to make a polyolefin by a borane or borate activatablemetal-organic compound, the halide groups of the metal-organic compoundfrom the process of the invention have to be alkylated or arylated in anadditional reaction step. This can be done for example with anorganolithium compound or an organo-magnesium compound. Surprisingly ithas been found that such alkylated or arylated metal-organic compoundcan also be prepared in one step by the process of the invention bycarrying out the process in the presence of at least 3, respectively 4equivalents of an organomagnesium compound or an organolithium compoundas a base. This holds for a metal-organic reagent comprising 3 halogenligands reacting with 1 imine functionality only. One skilled in the artwill understand that metal-organic reagents with 4 or 5 halogen ligandswill require at least 4 respectively 5 equivalents of a base in stead ofat least 3; or 5 respectively 6 equivalents in stead of 4.

The process of the invention is preferably carried out in a solvent.Suitable solvents are solvents that do not react with the metal-organicreagent or the metal-organic compound formed in the process of theinvention. Examples of suitable solvents include aromatic and aliphatichydrocarbons, halogenated hydrocarbons, amides of the aliphaticcarboxylic acids and primary, or secondary amines, DMSO, nitromethane,acetone, acetonitrile, benzonitrile, ethers, polyethers, cyclic ethers,lower aromatic and aliphatic ethers, esters, pyridine, alkylpyridines,cyclic and primary, secondary or tertiary amines, and mixtures thereof.Preferred solvents include aromatic or aliphatic hydrocarbons ormixtures thereof.

The process of the invention can be carried out, by adding at least 1,respectively at least 2 equivalents of a base to a mixture of the imineligand or its HA adduct and the metal-organic reagent thus forming areaction mixture. The desired metal-organic compound is often formedinstantaneously. Excess of a base may be applied without negativeeffects on the reaction product. The process of the invention ispreferably carried out in the presence of 1 equivalent of a base withrespect to the imine ligand, or 2 equivalents in the event that the HAadduct of the imine ligand.is used. Surprisingly it turned out that thereaction even with only one equivalent of an organic base appeared to beinstantaneously at room temperature to quantitative conversion. Anotheradvantage of a process of the invention in the presence of only oneequivalent of a base, is that the resulting compound may have a higheractivity. Without being bound to an explanation, this may be aconsequence of the fact that the formation of a coordination complex ofthe organic base with the metal-organic compound is prevented.

During the reaction, a salt is formed. The reaction mixture as obtainedby contacting an imine or its HA adduct with a metal-organic reagent inthe presence of a base, may be used as precatalyst in a polyolefinpolymerisation without an additional purification step if the saltformed during the reaction is compatible with the polymerisationprocess. A purification step is understood to be a filtration, acrystallization or a precipitation. Preferably the purification is afiltration step. If a salt free metal-organic compound is required, thesalt can be removed by using a filtration step. Depending on thesolubility of the metal-organic compound, the mixture may be heated andthen filtered. An advantage of the present invention is that thefiltrate may be used as such without further purification in a followingprocess, such as an alkylation or arylation step or the polymerisationprocess. If desired, the metal-organic compound may be isolated bydistillation of the solvent, by precipitation or by crystallisation froma suitable solvent.

The invention further relates to a process for the preparation of apolyolefin as described in claim 13. Such an olefin polymerisation canbe carried out in solution, slurry or in the gas phase.

In a preferred embodiment of the olefin polymerisation the (alkylated)metal-organic compound is formed in situ. By in situ preparation ismeant in this context, that the metal-organic compound is made andsubsequently activated in or anywhere before the reactor of thepolymerisation equipment by contacting an imine or its HA adduct with anmetal-organic reagent in the presence of an olefin polymerisationcompatible base. In the in situ preparation of the metal-organiccompound, it turned out to be favourable to use a surplus of ligand. Thenumber of ligands which are effectively bound to the metal ion are thendetermined by the number of equivalents of the base. In this case the“number of equivalents of a base” should then be read as the number ofequivalents of a base with respect to the equivalents of the ligandsbeing bound to the metal ion. Examples of bases compatible with theolefin polymerisation process include amines, organomagnesium compound,organolithium reagents, organozinc reagents, organoaluminum reagents.More preferred bases are: aromatic amines, organomagnesium compound,organolithium reagents, organozinc reagents, organoaluminum reagents.Most preferred bases are N,N-dimethylaniline, diphenylmethylamine,triphenylamine, dibutylmagnesium, n-butyllithium, C₁-C₂₀dihydrocarbylzinc derivatives, diisobutylaluminium hydride, C₁-C₂₀trihydrocarbyl aluminiums, or aluminoxanes. In the case wherealuminoxanes are applied as a base, the base can be the activator.

In the olefin polymerisation according to the invention, R preferablyrepresents a hydrogen atom and Y is preferably a substituent accordingto formula 3 of claim 2.

Advantages of the process of the invention are: mild conditions,avoidance of (ultra) cooling steps, higher yields, higher reaction ratesand smaller amounts of by-products. The (alkylated) metal-organiccompounds as obtained by the invented process can be used withoutfurther purification in the olefin polymerisation resulting in moreactive catalysts.

The invention will be elucidated with some non-limiting examples:

General Part

Experiments were performed under a dry and oxygen-free nitrogenatmosphere using Schlenk-line techniques. ¹H-NMR and ¹³C-NMR-spectrawere measured on a Bruker Avance 300 spectrometer. Diethyl ether andligroin were distilled from sodium/potassium alloy; THF and toluene frompotassium and sodium, respectively, all having benzophenone asindicator.

Tri-ethylamine was distilled from calciumhydride before use.

Other starting materials were used as obtained.

Part A Examples related to the preparation of the preparation of themetal-organic compound.

EXAMPLE I Synthesis of 1,3-bis(2,6-dimethylphenyl)-iminoimidazolineCyclopentadienyl Titanium Dichloride

To a suspension of 1,3-bis(2,6-dimethylphenyl)-iminoimidazoline (1.50 g,5.0 mmol) (prepared according to the procedure by L. Toldy et al, U.S.Pat. No. 4,284,642), and cyclopentadienyltitanium trichloride (1.10 g, 5mmol) in toluene (80 mL) was added triethylamine (1.0 mL, 7.2 mmol) atambient temperature. After stirring for 1 hour, the suspension washeated to reflux, then filtered hot. Cooling to ambient temperature gaveorange crystals, which were filtered, washed with cold toluene and dried(1.36 g, 57% yield). Partial evaporation of the mother liquor andcooling to −20° C. afforded another 0.90 g (38%). Total yield of1,3-bis(2,6-dimethylphenyl)-iminoimidazoline cyclopentadienyl titaniumdichloride was 95%.

EXAMPLE II Synthesis of 1,3-bis(2,6-dimethylphenyl)-iminoimidazolineCyclopentadienyl Titanium Dimethyl

To a suspension of 1,3-bis(2,6-dimethylphenyl)-iminoimidazoline (5.86 g,20.0 mmol) and cyclopentadienyltitanium trichloride (4.39 g, 20.0 mmol)in toluene (200 mL) was added triethylamine (2.53 g, 25 mmol) at ambienttemperature. After stirring for 1 hour at ambient temperature, the thickyellow-orange suspension was heated to reflux and filtered hot. Theyellow residue was extracted with boiling toluene portions of 10 mL 4times (leaving a grey-white residue). The combined orange filtrates(separating yellow-orange crystals upon cooling) were cooled to 0° C.Methyl magnesium bromide (14 mL of a 3.0 M solution in diethyl ether, 44mmol) was added in 10 minutes. The orange suspension turned yellowgradually. The mixture was stirred overnight, then evaporated todryness. The residue was extracted with boiling ligroin (200 mL) and theresulting suspension was filtered hot. Cooling to approx. −20° C.afforded yellow crystals, which were filtered and washed with coldligroin to give 2.8 g (32% yield) of NMR pure product. From thepartially evaporated mother liquor and 2^(nd) ligroin extract, a 2^(nd)fraction of pure product was obtained (1.0 g, 11%). Total yield of1,3-bis(2,6-dimethylphenyl)-iminoimidazoline cyclopentadienyl titaniumdimethyl was 43%.

EXAMPLE III Synthesis of 1,3-bis(2,6-dimethylphenyl)-iminoimidazolineCyclopentadienyl Titanium Dimethyl Using Methylmagnesium Bromide as Base

To a suspension of 1,3-bis(2,6-dimethylphenyl)-iminoimidazoline (2.93 g,10.0 mmol) and cyclopentadienyltitanium trichloride (2.19 g, 10.0 mmol)in toluene (100 mL) was added methylmagnesiumbromide (11 mL of a 3.0 Msolution in diethyl ether, 33 mmol) at −80° C. during 10 minutes. Themixture was allowed to warm to ambient temperature to give a yellowsuspension. THF (30 mL) was added, and the mixture was stirred for 15hours. The light yellow suspension was evaporated to dryness. Theresidue was extracted with boiling ligroin (100 mL). The resultingsuspension was filtered hot. The cake was extracted further with hotligroin (Three times with 60 mL until the filtrate became colourless).The combined yellow filtrates were partially evaporated under reducedpressure to 50 mL. Cooling to approx. 4° C. afforded yellow crystals,which were filtered and washed with cold ligroin to give 2.05 g (47%yield) of NMR pure 1,3-bis(2,6-dimethylphenyl)-iminoimidazolinecyclopentadienyl titanium dimethyl.

EXAMPLE IV Synthesis of 1,3-bis(2,6-diisopropylphenyl)-iminoimidazolineCyclopentadienyl Titanium Dichloride

-   a. Synthesis of 1,3-bis(2,6-diisopropylphenyl)-iminoimidazoline    -   To a mixture of 2,6-diisopropylaniline (260 g, 1.47 mol) in        ethanol (1200 mL) was slowly added glyoxal (108.5 g of a 40 w-%        in water solution, 0.75 mol). The solution turned intensely red,        then intensely yellow. The mixture was heated to reflux        overnight. Cooling to 4 degrees resulted in crystallisation of        yellow material, which was filtered and washed with cold ethanol        until filtrate became bright yellow (instead of brown). The        bright yellow powder was dried (202.6 g, 72%). This diimine (100        g, 0.27 mol) was dissolved in ethanol (1000 mL). The mixture was        cooled to 0° C. Sodium borohydride (102.1 g, 2.7 mol) was added        in portions during 1 hour. The mixture was allowed to warm to        room temperature, then stirred 1 hour. The mixture was heated to        reflux gently (gas evolution!) and heated to reflux for 1 hour.        After cooling, the mixture was admixed with water (2L), and the        suspension filtered. The yellow precipitate was dried (100.1 g,        98%).    -   57 g (0.15 mol) of the diamine was dissolved in toluene (250 mL)        and heated to reflux. A solution of cyanogen bromide (19.1 g,        0.18 mol) in toluene (100 mL) was added during the course of −1        hour, resulting in formation of a grey precipitate in an        orange-red solution. After stirring at reflux for 1 hour, the        mixture was cooled. The precipitate was filtered, washed with        toluene and ligroin (to give 47.1 g yellow light powder). This        powder was dissolved in water/ethanol 400/500 mL, and 10.0 M        NaOH in water was added until strongly basic (pH>10). The        precipitate was filtered and washed with water, then dried to        give 37.3 g (61.4% yield) of near pure product. The        iminoimidazoline can be crystallized to give pure material as        colourless crystals from boiling ligroin (270 mL) and filtering        hot to remove some insoluble material (recovery 67%).-   b. Synthesis of 1,3-bis(2,6-diisopropylphenyl)-iminoimidazoline    cyclopentadienyl titanium dichloride    -   To a suspension of        1,3-bis(2,6-diisopropylphenyl)-iminoimidazoline (1.02 g, 2.5        mmol) and cyclopentadienyltitanium trichloride (0.55 g, 2.5        mmol) in toluene (20 mL) was added triethylamine (0.4 mL, 4.0        mmol) at ambient temperature. After stirring for 2 hours, the        thick yellow-orange suspension was filtered, and the filtrate        evaporated to dryness to afford 1.31 g (89% yield) of NMR-pure        1,3-bis(2,6-diisopropylphenyl)-iminoimidazoline        cyclopentadienyltitanium dichloride.-   c. Synthesis of 1,3-bis(2,6-diisopropylphenyl)-iminoimidazoline    cyclopentadienyl titanium dichloride (reversed addition)    -   The same result as under b. was obtained when        cyclopentadienyltitanium trichloride and triethylamine were        admixed in toluene, and then ligand was added.-   d. Synthesis of 1,3-bis(2,6-diisopropylphenyl)-iminoimidazoline    cyclopentadienyl titanium dichloride

To a suspension of 1,3-bis(2,6-diisopropylphenyl)-iminoimidazoline (2.03g, 5.0 mmol) and cyclopentadienyltitanium trichloride (1.10 g, 5.0 mmol)in toluene (30 mL) was added triethylamine (0.8 mL, 5.7 mmol) at ambienttemperature. After stirring for 1 hour, the thick yellow-orangesuspension was diluted with toluene (50 mL) and ligroin (120 mL). Thesuspension was heated to reflux and filtered hot. Cooling to approx. 4°C. afforded yellow crystals, which were filtered and washed with coldligroin to give 1.34 g (46% yield) of NMR pure1,3-bis(2,6-diisopropylphenyl)-iminoimidazoline cyclopentadienyltitanium dichloride.

EXAMPLE V Synthesis of 1,3-bis(2,6-diisopropylphenyl)-iminoimidazolineCyclopentadienyl Titanium Dimethyl

To a suspension of 1,3-bis(2,6-diisopropylphenyl)-iminoimidazoline (2.06g, 5.0 mmol) and cyclopentadienyltitanium trichloride (1.10 g, 5.0 mmol)in toluene (40 mL) was added triethylamine (0.8 mL, 5.7 mmol) at ambienttemperature. After stirring for 2 hours, the thick yellow-orangesuspension was filtered, and the residue washed with toluene. The clearand orange filtrate was partially evaporated (˜10 mL solvent removed).After cooling to −78° C. (dry ice/acetone), methyl magnesium bromidesolution (3.3 mL of a 3M solution in diethyl ether, 10.0 mmol) wasadded. The temperature of the mixture was allowed to rise to ambienttemperature and the mixture was stirred overnight. The yellow suspensionwas evaporated to dryness. The residue was extracted with boilingligroin (80 mL) and the resulting suspension was filtered hot.Evaporation to −30 mL and cooling to approx. 4° C. afforded yellowcrystals, which were filtered and washed with cold ligroin to give 1.38g (51% yield) of NMR pure product. From the partially evaporated motherliquor, a 2^(nd) fraction of pure1,3-bis(2,6-diisopropylphenyl)-iminoimidazoline cyclopentadienyltitanium dimethyl was obtained (0.58 g, 19%). Total yield of1,3-bis(2,6-diisopropylphenyl)-iminoimidazoline cyclopentadienyltitanium dimethyl: 70%.

EXAMPLE VII Synthesis ofBis(1-N-cyclohexylcarboximino-6-t-butylphenoxy)titaniumdichloride

To a solution of titanium(IV) chloride (5 mL, 1.0M in toluene, 5.0 mmol)in toluene (40 mL) was added 1-N-cyclohexylcarboximine-6-t-butylphenol(2.59 g, 10.0 mmol) and triethylamine (1.02 g, 10 mmol) subsequently.The reaction mixture was stirred for 16 hours at room temperature. Thesolid was allowed to precipitate and the supernatant was decanted. Theremaining solid was extracted twice with a mixture of toluene/THF (80mL, 1/1, V/V). The solvents were removed in vacuo resulting in 2.80 g(88%) of a red solid. NMR data were consistent with those reported inEP0874005, but the yield of 88% is substantially higher than the 18%yield reported in EP 0874005.

EXAMPLE VIII Synthesis ofBis(1-N-cyclohexylcarboximino-6-t-butylphenoxy)zirconiumdichloride

To zirconium(IV) chloride (1.40 g, 4.5 mmol) was added THF (40 mL). Themixture was cooled to 0° C. and a solution of1-N-cyclohexylcarboximine-6-t-butylphenol (2.31 g, 8.9 mmol) in toluene(25 mL) was added. Then, triethylamine (0.89 g, 8.9 mmol) was added andthe mixture was stirred for 15 hours at room temperature. The solidswere allowed to precipitate and the supernatant was decanted from thesolid. The solid was extracted with a mixture of toluene/THF (80 mL,1/1, V/V). The combined extracts were evaporated to dryness resulting in2.95 g (97%) of a light yellow powder. NMR data were consistent withthose reported in EP0874005, but the yield was significantly higher thanthe yield of 43% reported in EP 0874005.

Part B Examples Related to the Polymerisation of an Olefinic Copolymer.

Polymerisation Equipment.

The batch copolymerisation was carried out in a polymerisationequipment, having a catalyst dosing vessel equipped with a catalystdosing pump for the addition of the catalyst to a 2-liter batchautoclave equipped with a double intermig stirrer and baffles. Thereactor temperature was controlled by a Lauda Thermostat. The feedstreams (solvents and monomers) were purified by contacting them withvarious absorption media as is known in the art. During polymerisation,the ethylene (C2) and propylene (C3) were continuously fed to the gascap of the reactor. The pressure of the reactor was kept constant bymeans of a back-pressure valve.

Copolymerisation Experiments.

In an inert atmosphere of nitrogen, the reactor was filled withpentamethylheptanes (PMH) (950 mL) and an amount of MAO (Crompton 10 wt% in toluene) and 4-methyl-2,6-di-tert-butylphenol (BHT) as given inTables 1 and 2. The reactor was heated to 90° C., while stirring at 1350rpm. The reactor then was pressurized to 0.7 MPa and kept under adetermined flow of 200 NL/h of ethylene and 400 NL/h of propylene for 15minutes. Then, the catalyst components were added to the reactor andpossible residual material was rinsed with PMH (50 mL) andsubsequently-fed to the reactor.

When tritylium tetrakis(perfluorophenyl)borate (THF20) was used, theTHF20 was added directly after the catalyst addition. After 10 minutesof polymerisation, the monomer flow was stopped and the solution wasslowly poured into a 2 L Erlenmeyer flask, and dried over-night at 100°C. under reduced pressure. The polymers were analysed by FT-IR todetermine the amount of incorporated C3 and Intrinsic Viscosity being anindication for the average molecular weight.

Polymer Analysis.

The amount of incorporated C3 in weight per cents relative to the totalcomposition, was measured by means of Fourier transformation infraredspectroscopy (FT-IR) according to ASTM D 3900 method A.

The Intrinsic Viscosity (IV) was measured at 135° C. in decaline.

EXAMPLES 2-15 In Situ Polymerisation

These catalysts were prepared in the polymerisation equipment by addingamounts as depicted in table 1a of toluene solutions of themetal-organic reagent, the ligand and the base successively to thecatalyst dosing vessel in toluene (15 mL). After stirring for 5 minutes,the mixture was injected into the polymerisation reactor. Results areshown in Table 1b.

The experiments 2, 5, 12 and 13 were carried out by adding a preparedand purified metal-organic compound to the catalyst dosing vessel, andsubsequently fed to the polymerisation reactor.

It can be concluded from the comparison of all experiments withexperiment 2, that all in situ prepared catalysts produce copolymershaving a higher molecular weight than the copolymer produced with theCpTiCl₃ and the base only, which allows preparation of a polyolefin byjust adding a metal-organic reagent, an imine ligand and at least 1equivalent of a base to the polymerisation equipment.

From Examples 8 and 10 it can be concluded that a process in thepresence of between 5 and 10 equivalents of the imine ligand accordingto formula 1 is mostly preferred.

TABLE 1a In situ polymerisations: polymerisation conditions Metal-Metal-organic organic compound Ligand Base Al/Ti BF20/Ti Pol. reagent/dosage dosage dosage Activator Molar Molar BHT/Al Time Example compound(μmol Ti) ligand (μmol) Base (μmol) system ratio ratio Molar ratio (min)2 CpTiCl3 0.75 — — Et3N 0.75 MAO/BHT 3000 — 1 10 5 2 0.05 — — — —MAO/BHT 3000 — 1 10 6 CpTiCl3 0.75 L2 1.5 Et3N 0.75 MAO/BHT 3000 — 1 107 CpTiCl3 0.75 L2 0.75 Et3N 0.75 MAO/BHT 3000 — 1 10 8 CpTiCl3 0.75 L23.75 Et3N 0.75 MAO/BHT 3000 — 1 10 10 CpTiCl3 0.25 L2 2.5 Et3N 0.25MAO/BHT 3000 — 1 10 11 CpTiCl3 0.4 L2 2 Et3N 0.4 MAO/BHT/ 3000 2 1 3TBF20 12 TiCl4 5 — — Et3N 10 MAO/BHT 250 — 1 10 13 3 5 — — — — MAO/BHT250 — 1 10 14 TiCl4 5 L3 10 Et3N 10 MAO/BHT 250 — 1 10 15 TiCl4 5 L3 10— — MAO/BHT 250 — 1 10 Metal-organic compound 2 =1,3-bis(2,6-dimethylphenyl)-iminoimidazoline cyclopentadienyl titaniumdibenzyl Metal-organic compound 3 =Bis(1-N-cyclohexylcarboximino-6-t-butylphenoxy)titaniumdichloride L2 =1,3-bis(2,6-dimethylphenyl)-iminoimidazoline L3 =1-N-cyclohexylcarboximine-6-t-butylphenol

TABLE 1b In situ polymerisations: polymerisation results residualIncorpo- Ti in rated ΔT Yield polymer C3⁼ IV Example (° C.) (g) (ppm)(wt %) (dl/g) 1 0.8 2.93 8.2 41 2.4 2 0.5 2.74 13.1 62 0.96 3 3.5 8.975.3 46 Nd 4 1.6 5.34 3.6 42 Nd 5 1.8 6.09 0.4 48 2.77 6 2.0 8.41 4.3 542.07 7 0.8 3.76 9.5 8 4.2 14.37 2.5 51 2.32 10 4.9 19.84 0.6 52 2.29 114.4 18.05 1.1 50 12 0.6 0 13 1.3 3.55 67.4 1.67 14 1.1 3.18 75.3 1.65 151.2 2.89 82.8 1.72

EXAMPLES 19-20 Polymerisation with Unpurified1,3-bis(2,6-dimethylphenyl)-iminoimidazoline Cyclopentadienyl TitaniumDichloride

Catalyst Preparation

Cyclopentadienyltitaniumtrichloride (75 mg, 0.34 mmol) and1,3-bis(2,6-dimethylphenyl)-iminoimidazoline (0.10 g, 0.34 mmol) weremixed in toluene (10 mL). Triethylamine (34 mg, 0.34 mmol) was added andthe reaction mixture was stirred at room temperature for 2 hours.

Polymerisation

For the polymerisation an aliquot (0.75 mL) of the mixture obtainedabove was diluted with toluene (25 mL). From this diluted mixture, analiquot (0.15 mL) was added to the catalyst dosing vessel containing PMH(15 mL). This mixture was subsequently added to the polymerisationreactor and the catalyst dosing vessel was rinsed with PMH (50 mL).Examples 19-20 indicate that polymerisation of olefinic monomers ispossible by just adding a mixture of a metal-organic reagent, an imineligand and at least one equivalent of a base to a polymerisation reactorwith olefinic monomers, without the need to firstly purify (i.cfiltrate) a catalyst (i.c. metal-organic compound) from the mixture.

TABLE 2a Polymerisation with unpurified catalysts: polymerisationconditions Metal- organic BF20/ BHT/ Metal- compound Al/Ti Ti Al Pol.Exam- organic dosage Activator Molar Molar Molar Time ple compound (μmolTi) system ratio ratio ratio (min) 19 5 0.15 MAO/BHT 3000 — 1 10 20 50.15 MAO/BHT 3000 — 1 10 Metal-organic compound 4 =triisopropylphosphoraneimido cyclopentadienyl titanium(IV) dichlorideMetal-organic compound 5 = 1,3-bis(2,6-dimethylphenyl)-iminoimidazolinecyclopentadienyl titanium dichloride Metal-organic compound 6 =triisopropylphosphoraneimido cyclopentadienyl titanium(IV) dimethyl

TABLE 2b Polymerisation with unpurified catalysts: polymerisationresults residual Incorpo- Ti in rated ΔT Yield polymer C3⁼ IV Example (°C.) (g) (ppm) (wt %) (dl/g) 19 4.8 18.75 0.4 501 2.33 20 4.2 16.5 0.4 53nd

1. A process for the preparation of a metal-organic compound, comprisingat least one imine ligand, characterized in that an imine ligandaccording to formula 1 or the HA adduct thereof, wherein HA representsan acid, of which H represents its proton and A its conjugate base, iscontacted with a metal-organic reagent of formula 2 in the presence ofat least 1, respectively at least 2 equivalents of a base, withY═N—R  as formula 1, wherein Y is selected from a substituted carbon, ornitrogen atom and R represents a substituent, and withM^(v)(L₁)_(k)(L₂)_(l)(L₃)_(m)(L₄)_(n)X  as formula 2, wherein: Mrepresents a group 4 or group 5 metal ion V represents the valency ofthe metal ion, being 3, 4 or 5 L₁, L₂, L₃, and L₄ represent a ligand ora group 17 halogen atom on M and may be equal or different, X representsa group 17 halogen atom, k, l, m, n=0, 1, 2, 3, 4 with k+l+m+n+l=V.
 2. Aprocess according to claim 1 wherein R represents a hydrogen atom andwherein Y is represents a substituent defined by formula 3:

wherein each of Sub¹ and Sub² is independently selected from the groupconsisting of hydrocarbyl radicals having from 1 to 30 carbon atoms;silyl radicals, (substituted) amido radicals and (substituted) phosphidoradicals, and wherein Sub¹ and Sub² may be linked with each other toform a ring system.
 3. A process according to claim 1, wherein the baseis an amine or a phosphane.
 4. A process according to claim 1, whereinthe base is a dialkylamine, a trialkylamine, a monoarylamine,diarylamine or a triarylamine.
 5. A process according to claim 1,wherein the base is triethylamine, pyridine, tripropylamine,tributylamine, 1,4-diaza-bicyclo[2.2.2]octane, pyrrolidine orpiperidine.
 6. A process for the preparation of a metal-organiccompound, comprising at least one imine ligand, characterized in that animine ligand according to formula 1 or the HA adduct thereof, wherein HArepresents an acid, of which H represents its proton and A its conjugatebase, is contacted with a metal-organic reagent of formula 2 in thepresence of at least 1, respectively at least 2 equivalents of a base,withY═N—R  as formula 1, wherein Y is selected from a substituted carbon, ornitrogen atom and R represents a substituent, and withM^(v)(L₁)_(k)(L₂)_(l)(L₃)_(m)(L₄)_(n)X  formula 2, wherein: M representsa group 4 or group 5 metal ion V represents the valency of the metalion, being 3, 4 or 5 L₁, L₂, L₃, and L₄ represent a ligand or a group 17halogen atom on M and may be equal or different, X represents a group 17halogen atom, k, l, m, n=0, 1, 2, 3, 4 with k+l+m+n+l=V, wherein thebase is a carboxylate, a fluoride, a hydroxide, a cyanide, an amide, acarbonate of Li, Na, K, Rb, Cs, or an ammonium salt or a group 2 metalsalt of Mg, Ca, or Ba thereof, an alkali metal (Li, Na, K, Rb, Cs)phosphate, or phosphate ester, or their alkoxide or phenoxides, thalliumhydroxide, alkylammonium hydroxides or fluorides, or alkali metals,hydrides or carbonates of Li, Na, K, Rb, Cs or group 2 hydrides.
 7. Aprocess according to claim 6, wherein the alkali metal is chosen fromLi, Na, or K.
 8. A process for the preparation of a metal-organiccompound, comprising at least one imine ligand, characterized in that animine ligand according to formula 1 or the HA adduct thereof, wherein HArepresents an acid, of which H represents its proton and A its conjugatebase, is contacted with a metal-organic reagent of formula 2 in thepresence of at least 1, respectively at least 2 equivalents of a base,withY═N—R  as formula 1, wherein Y is selected from a substituted carbon, ornitrogen atom and R represents a substituent, and withM^(v)(L₁)_(k)(L₂)_(l)(L₃)_(m)(L₄)_(n)X  as formula 2 wherein: Mrepresents a group 4 or group 5 metal ion V represents the valency ofthe metal ion, being 3, 4 or 5 L₁, L₂, L₃ and L₄ represent a ligand or agroup 17 halogen atom on M and may be equal or different, X represents agroup 17 halogen atom, k, l, m, n=0, 1, 2, 3, 4 with k+l+m+n+l=V,wherein the base is a group 1, 2, 12,13 hydrocarbanion.
 9. A processaccording to claim 8, wherein the base an organomagnesium- or anorganolithium compound.
 10. A process for the preparation of ametal-organic compound, comprising at least one imine ligand,characterized in that an imine ligand according to formula 1 or the HAadduct thereof, wherein HA represents an acid, of which H represents itsproton and A its conjugate base, is contacted with a metal-organicreagent of formula 2 in the presence of at least 1, respectively atleast 2 equivalents of a base, withY═N—R  as formula 1, wherein Y is selected from a substituted carbon, ornitrogen atom and R represents a substituent, and withM^(v)(L₁)_(k)(L₂)_(l)(L₃)_(m)(L₄)_(n)X  as formula 2, wherein: Mrepresents a group 4 or group 5 metal ion V represents the valency ofthe metal ion, being 3, 4 or 5 L₁, L₂, L₃, and L₄ represent a ligand ora group 17 halogen atom on M and may be equal or different, X representsa group 17 halogen atom, k, l, m, n=0, 1, 2, 3, 4 with k+l+m+n+l=V,wherein said process is carried out in the presence of at least 3respectively 4 equivalents of an organolithium- or an organomagnesiumcompound.
 11. A process for the preparation of a metal-organic compound,comprising at least one imine ligand, characterized in that an imineligand according to formula 1 or the HA adduct thereof, wherein HArepresents an acid, of which H represents its proton and A its conjugatebase, is contacted with a metal-organic reagent of formula 2 in thepresence of at least 1, respectively at least 2 equivalents of a base,withY═N—R  as formula 1, wherein Y is selected from a substituted carbon, ornitrogen atom and R represents a substituent, and withM^(v)(L₁)_(k)(L₂)_(l)(L₃)_(m)(L₄)_(n)X  as formula 2 wherein: Mrepresents a group 4 or group 5 metal ion V represents the valency ofthe metal ion, being 3, 4 or 5 L₁, L₂, L₃, and L₄ represent a ligand 17halogen atom on M and may be equal or different, X represents a group 17halogen atom, k, l, m, n=0, 1, 2, 3, 4 with k+l+m+n+l=V, wherein thereaction is carried out in an aprotic solvent.
 12. A process accordingto claim 11, wherein the solvent is the base.
 13. Process for thepreparation of a polyolefin by making a metal-organic compound accordingto the process of claim 1, wherein the base is an olefin polymerisationcompatible base, which metal-organic compound is activated anywhere in,or before a polymerisation equipment.
 14. Process according claim 13,wherein the metal-organic compound is formed used without purification.15. Process according to claim 13, wherein the metal-organic compound isformed in the polymerisation equipment.
 16. Process according to claim15, in the presence of between 5 and 10 equivalents of the imine or itsHA adduct according to formula 1.